<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .box0{
            width:1000px;
            margin: 0 auto;
            /* overflow: hidden; */
        }
        .box1{
            height: 100px;
            width: 1000px;
            margin: 0 auto;
            background-color: red;
            float: left;
            margin-bottom: 20px;
        }
        .box23{
            width: 1000px;
        }
        .box2{
            height: 800px;
            width: 200px;
            background-color: sienna;
            float: left;
        }
        .box3{
            height: 800px;
            width: 560px;
            background-color: seagreen;
            float: left;
            margin-left: 20px;
            margin-right: 20px;
        }
        .box4{
            height: 800px;
            width: 200px;
            background-color: yellow;
            float: left;
        }
        .box5{
            height: 150px;
            width: 1000px;
            float: left;
            background-color: cadetblue;
            margin-top: 20px;
        }
        .clearfix::after{
            content: "";
            clear: both;
            display: block;
        }
    </style>

</head>
<body>
    <div class="box0">
        <div class="box1"></div>
        <div class="clearfix" class=box23>
            <div class="box2"></div>
            <div class="box3"></div>
            <div class="box4"></div>
        </div>
    <div class="box5"></div>
    </div>
    </div>
</body>
</html>